Window braking mechanism



J: W. SCOTT March 24, 1970 OW BRAKING MECHANISM '2 Sheets-Sheet 1 Filed Oct. 22, 1968 HV/ V/AV March 24, 1970 Filed Oct. 22, 1968 J. w. SCOTT I WINDOW BRAKING MECHANISM 2 Sheets-Sheet 2 United States Patent 3,501,867 WINDOW BRAKING MECHANISM John W. Scott, 1510 Johanna St., Houston, Tex. 77055 Continuation-impart of application Ser. No. 580,429,

Sept. 19, 1966. This application Oct. 22, 1968, Ser.

Int. Cl. Ed 13/08 US. Cl. 49-421 13 Claims ABSTRACT OF THE DISCLOSURE A braking device for holding a window sash at a predetermined point along a generally U-shaped side jamb of a window frame which includes a housing which can be mounted along the top rail of a singleor double-hung window sash or the bottom rail of a single-hung sash or in the side rail of such sashes. The housing contains at least one spring-biased braking element 'operatively expansible and contractible in position to vary the frictional contact between the braking element and the inside of the U- shaped jamb of the window frame and a limit element in contact with the braking element and adjustable to limit the expansion of the braking element and thus vary the maximum frictional contact between the braking element and the side jamb.

RELATED APPLICATION The present application is a continuation-in-part of application Ser. No. 580,429, now Patent No. 3,407,434, entitled Window Balance, filed by the present inventor on Sept. 19, 1966.

BACKGROUND OF THE INVENTION The present invention is directed to a braking device for singleand double-hung windows. In a more specific aspect, the present invention is directed to a frictionally operative braking device for singleand double-hung windows which may be conveniently mounted on the top rail of singleor double-hung windows, to the bottom rail of single-hung windows or in the side rail of such windows and in which the maximum frictional force may be varied.

In the prior art there are numerous braking devices for singleand double-hung windows which rely upon springs, counterweights and the like. However, all of these devices are of complex construction and require considerable maintenance.

Accordingly, it is an object of the present invention to provide a braking device which may be mounted on the sashes of singleor double-hung windows with the channel formed by the frame jambs providing a braking surface for the device.

Another object of the present invention is to provide a window braking device which offers no obstruction to view and permits maximum opening of the window.

A still further object of the present invention is to provide a window braking device which is relatively wear proof and is easily replaceable by the home owner in the unlikely event of failure.

Another and further object of the present invention is to provide a window braking device which offers the manufacturer the advantages of eliminating many costly operations, reduces his inventory requirement, eliminates balance failure in handling and shipping and eliminates costly field maintenance and repairs.

Yet another object of the present invention is to provide a window braking device, wherein a single unit may be mounted on either side or the top or bottom of a sash frame.

3,501,867. Patented Mar. 24, 1970 SUMMARY OF THE INVENTION Briefly, in accordance with the present invention, a braking device for holding a window sash at a predetermined point along a generally U-shaped side jamb is provided in which at least one braking element, adapted to frictionally engage at least one of the inner surfaces of the side jamb, is normally spring-biased against the jamb surface, this braking element being mounted to create a wedging action in an upward direction, which increases the frictional pressure when the weight of the window is applied thereto; and an adjustable limit means, adapted to adjust the maximum frictional pressure which the brake element can apply against the jam surface, is mounted in contact with the braking element. In operation, the braking element follows an upwardly inclined path toward the jamb surface and the limit means limits the maximum distance along this path which the braking element may travel.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIGURE 1 is a front view, partially in section, of a window frame and jamb with one form of the braking mechanism of the present invention mounted on the Window frame;

FIGURE 2 is a side view of the mechanism of FIG- URE 1;

FIGURE 3 is a front view, partially in section, of a window frame and jamb having another form of the braking mechanism of the invention mounted in the side frame of the window;

FIGURE 4 is a side view, partially in section, of a window frame and window jamb with a modified form of the braking element of the present invention mounted in the side frame of the window;

FIGURE 5 is a top view showing the details of the braking mechanism illustrated in FIGURES 1, 2, and 3;

FIGURE 6 is a front view of the mechanism of FIG- URE 5;

FIGURE 7 is a cross-sectional View taken along the lines 77 of FIGURE 6;

FIGURE 8 is a front view showing the details of the braking mechanism illustrated in FIGURE 4;

FIGURE 9 is a top view of the mechanism of FIGURE 8; and

FIGURE 10 is a top view of the brake element of FIGURE 8.

DETAILED DESCRIPTION In accordance with FIGURES 1 and 2, a side window jamb 10 having a general U-shape with the numeral 12 designating the interior surface of the base of the U, while numerals 14 and 16 indicate the interior surface of the legs of the U. Slideably mounted in jamb 10 is a window 18 having a side frame 20 and top frame 22. In these two figures, one embodiment of the window braking mechanism is mounted on top of top frame 22 of window 18 as by screws or other appropriate fastening means. The braking mechanism comprises generally, a frame or casing 24 whose ends are open to form a rectangular channel in its center. Mounted in the rectangular channel are braking elements 26 and 28, respectively. As will be pointed out in greater detail hereinafter, both friction blocks 26 and 28 are slideable within casing 24 and mounted below and urging block 26 upwardly is spring 30. Limiting the upward movement of friction block 26 is limit means 32 which, in this case, is a set screw. Casing 24 can also serve as a guide for the sash in the U-shaped channel. The details of the balance means of FIGURES 1 and 2 will be shown in the hereinafter described FIGURES 5, 6, and 7.

FIGURE 3 of the drawings shows another embodiment of the present invention. In accordance with FIGURE 3, the side jamb of the window is the same as in previous figures, as is the window 18. In this embodiment, however, the balance means is modified so that it may be mounted in a corner of frame 20-22 of window 18. For this purpose, a different casing 34 is provided which is substantially the same as casing 24, except that it does not have the side mounting leg. In other words, casing 24 in this instance is simply a rectangular, open-ended channel section. Otherwise, the interior elements including set screw 32, friction block 26 and spring 30 are exactly the same as in the previous drawings. Friction block 28 is also substantially the same except that it is not shown in FIGURE 3.

FIGURE 4 of the drawings illustrates still another embodiment in which a different type braking unit is mounted in the edge of a corner of side frame 20-22 of the window 18. In accordance with FIGURE 4, the brake casing 36 is a rectangular channel with its back end closed and only the front end open. While the details of the embodiment of FIGURE 4 will be shown in FIGURES 8, 9, and 10, the remaining elements shown in FIGURE 4 are essentially the same as in the previous drawings, there being a limit means or set screw 38, a friction block 40' which works against the base of the U-shaped side jamb and a spring 42.

FIGURES 5, 6, and 7 show the interior elements of the braking mechanism previously referred to in FIGURES 1, 2, and 3. For convenience, the same numbers are utilized in FIGURES 5, 6, and 7. Specifically, the interior mechanism involves a friction block 28 which works against one of the legs of the Window jamb and a friction block 26 which works against the other leg of the window jamb. Friction block 28 is generally L-shaped and may be the same size or smaller than the casing within which it fits. The upstanding portion of the L is inclined inwardly from the top to the bottom to form inclined surface 42. Inclined surface 42 is narrower than the remaining portion of the upstanding leg of friction block 28 to form rib or spline portion 44. Formed on rib section 44 and extending along a major portion of inclined surface 42 are flanges 46. Flanges 46, together with inclined surface 42, form an inclined support surface. Formed on the horizontal portion of L-shaped friction block 28 is a generally cylindrical upstanding knob 48. The bottom of spring 30 fits over knob 48. Friction block 26 is generally wedge-shaped except that side arms 50 extend therefrom. Formed on the ends of side arms 50 are cylindrical inward projections or knobs 52. It is to be noted from FIGURES 6 and 7 that the knobs 52 accommodate spline 44 of block 28 between them and therefore they may he slid over the bottom of spline 44 during the assembling of the device, but when they are slid upwardly past the elongated flanges 46, the flanges 46 will prevent block 26 from separating from block 28. The fit between knobs 52 and flanges 46 is such that a generally L-shaped slide element 54 may have its longest leg positioned between blocks 26 and 28 to act as a slide surface for block 26. Once friction element 54 is mounted, it is no longer possible to remove block 26 from its connection to block 28 without removing the slide element 54. Spring 30 has its upper end fitted into a cylindrical depression 56 in the bottom of block 26 and therefore normally urges block 26 upwardly at all times. The upward travel of block 26 is limited by limit means or set screw 32. Set screw 32 is threadably mounted through the casing of the braking mechanism and rests in elongated depression 58 on top of block 26. Thus, set screw 32 may be adjusted .to vary the maximum upward travel of friction block 26 and accordingly, the degree of frictional engagement between blocks 26 and 28 and the side legs of the U-shaped window jamb. It should also be noted that depression 58 in conjunction with screw 32 prevents the shoes from falling out of their casing prior to installation. As indicated, block 28 may be substantially the same height as the casing within which it fits, or it may be smaller than the opening of the casing. It should also be observed that the structure of the elements including previously mentioned casing 24) is such that all can be manufactured from molded plastic parts.

FIGURES 8, 9 and 10 show the details of the embodiment illustrated in FIGURE 4. In accordance with these figures, casing 36 has sides, a top and bottom and a back closure but the front is open and this type mechanism can therefore either be mounted with the block 40 against the base of the U-shaped jamb or against one of the side legs of the U-shaped jamb. Casing 36 has two elongated slots 56 formed in either side of the casing toward the rear of the casing. Slots 56 are generally inclined inwardly as they approach the bottom of the casing. A slide element 58 of substantially the same type as the previously described slide element 54 has its elongated leg passed through a slot 60 in the top of casing 36. Preferably, the short leg of slide element 58 is attached to casing 36 by means of screws 62. The long leg of slide element 58 is inclined inwardly toward the bottom of the casing and therefore acts as the primary sliding surface for block 40. Block 40, as shown in FIGURE 10, is provided with extended side arms 62. Side arms 62 are wide enough to accommodate slide element 58 and therefore during assembly, arms 62 are passed over slide element 58 and an elongated, cylindrical pin 64 is then passed through side arms 62 and extend into and work in slots 56 of casing 36. With some variations in the shape of friction block 40, the slide element 58 could be eliminated. However, the slide element adds a certain amount of stability which cannot be provided by pin 64 alone. It is obvious that the elongated leg of slide 58 could pass into a slot in the bottom of casing 36. The spring 42 is mounted on a cylindrical, upstanding knob 68 formed on the interior of the bottom of casing 36. Otherwise, spring 42 is mounted substantially the same as spring 30 of the previous embodiments. The limit means 38 is threadably mounted through the top of casing 36 and rests against the top of friction block 40 in the elongated depression 70, in substantially the same manner as in the previous embodiments.

The operation of the braking mechanism of the present invention will now be explained with specific reference to the mechanism shown in FIGURES 1, 2, 3, 5, 6 and 7. As previously indicated, the braking mechanism may be mounted on the top rail of the bottom sash of a doubleor single-hung window or on the bottom rail of the top sash of a double-hung window as shown in FIGURES 1 and 2. This same type of braking mechanism can also be mounted in the side frame of the window either after the window is manufactured or as a part of the window frame, as shown in FIGURE 3. In either event, the spring 30 normally biases brake element 26 upwardly along the inclined inner face of braking element 28, thereby expanding the braking mechanism laterally and increasing the frictional contact between the braking elements 26 and 28 and legs 14 and 16, respectively, of the window jamb. When the window frame is moved upwardly, the tension of spring 30 is overcome, braking element 26 is moved downwardly, and the frictional contact between braking elements 26 and 28 and the legs of the window jamb is minimized. However, when the window frame is released and the weight of the window is permitted to move the window downwardly, spring 30 moves braking element 26 upwardly along the incline to expand the braking element into greater frictional contact with the side legs of the Window jamb. This frictional resistance reaches a maximum when the friction element 26 is actually wedged between friction element 28 and the leg of the window jamb in contact with friction element 26 by the weight of the window. When this wed-ging action occurs, it will hold the window in position until the wedging force is released by a slight upward movement of the window frame, which movement in turn compresses the spring 30 slightly and decreases the frictional contact between the braking elements and the legs of the window jamb. It is, of course, also possible to completely overcome the frictional forces holding the window open by applying sufficient downward pressure on the window frame.

The maximum frictional pressure which can be applied by the brake shoes is limited by limit means 32 which, in the illustrated modifications, is a set screw. This set screw may be adjusted upwardly or downwardly to limit the relative upward movement of braking element 26. Thus, by moving screw 30 downwardly, the maximum frictional pressure can be reduced; whereas, by backing the screw 32 ofi, brake element 26 will be permitted to move upwardly a greater distance and thus increase the maximum frictional pressure. This limiting of the maximum frictional pressure is extremely important and has not heretofore been provided in simple window braking mechanisms such as that illustrated herein.

The operation of the modification shown in FIGURES 4, 8, 9 and is the same as that previously described with the exception that there is a single braking element or shoe 40. Otherwise, the operation is exactly the same.

While many modifications have been illustrated, others will occur to those skilled in the art. For example, a twoshoe braking mechanism can be mounted anywhere along the side frame of a window sash. It may be mounted on top as shown in FIGURES 1 and 2, in the top corner as shown in FIGURE 3, or anywhere along the side sash and the two shoes will contact the side legs of the U shaped jamb. W'hile FIGURE 4 shows the single shoe braking mechanism in contact with the base of the U-shaped jamb, this element may be turned 90 and used in substantially the same fashion as the two-shoe element shown in FIGURE 3. In other words, the shoe may work against either of the two side legs of the window jamb. Either of the two mechanisms may also be modified to eliminate slide surfaces 54 or 58 although convenience of assembly dictates the desirability of having a separate slide mech anism. Also, the slide mechanism 54 of FIGURES 5, 6, and 7 can be attached by screws to the top of brake element 28 in a manner similar to the attachment of slide element 58 to the casing of FIGURES 8 and 9. It is also possible to build the frame or casing sections as part of the window frame so that all that is necessary is to insert the braking element or elements and the spring and limit element. Further, in another obvious modification, the inclined slide mechanism 58 of FIGURES 8 and 9 can actually be a section of the window itself suitably inclined to receive the mating surface of brake element 40. It is obvious that other modifications and variations will occur to one skilled in the art.

I claim:

1. A device for holding a window sash at a predetermined point along a generally U-shaped side jamb of a window frame, comprising:

(a) at least one braking element mounted on said window sash adjacent the side thereof and in frictional contact with an inside surface of said side (b) said braking element being operatively expansible and contractible in position to vary said frictional contact between said braking element and said side jamb; and

(c) adjustable limit means in contact with said braking element and adapted to adjustably limit the maximum expansion of said braking element and accordingly the maximum value of said frictional contact between said braking element and said side 6 jamb, while, at the same time, leaving unaffected the ability of said braking element to contract and vary said frictional contact between said maximum and a lower minimum.

2. A device in accordance with claim 1 which additionally includes a spring means normally biasing the braking element in its expanded position.

3. A device in accordance with claim 1 wherein the first-mentioned braking element frictionally contacts one leg of the U-shaped side jamb and a second braking element is interlinked to said first braking element and frictionally contacts the opposite leg of said side jamb.

4. A device in accordance with claim 3 wherein the interlinking is such that the first and second braking elements are inseparable when the device is assembled but can be unlinked during disassembly.

5. A device in accordance with claim 3 wherein the two braking elements are mounted in a casing attached to the window sash.

6. A device in accordance with claim 1 wherein the limit means is a set screw having its free end in contact with the braking element.

7. A device for holding a window sash at a predetermined point along a generally U-shaped side jam'b of a window frame, comprising:

(a) at least one generally wedge-shaped braking element mounted on said window sash adjacent the side thereof, in frictional contact with an inside surface of said side jamb, and operatively slideable along an upwardly and outwardly inclined slide surface to wedge between said slide surface and said side jamb;

(b) said braking element being operatively expansible and contractible in position to vary said frictional contact between said braking element and said side jamb, and wedge said braking element between said slide surface and said side jamb when in its expanded position; and

(c) adjustable limit means in contact with said braking element and adapted to adjustably limit the maximum expansion of said braking element and accordingly the maximum value of said frictional contact between said braking element and said side jamb.

8. A device in accordance with claim 7 wherein the slide surface is formed in the Window sash.

9. A device in accordance with claim 7 wherein the slide surface is a separate element mounted in a casing for the brake element.

10. A device in accordance with claim 7 wherein the first-mentioned braking element frictionally contacts one leg of the U-shaped side jamb and a second wedgeshaped braking element is interlinked to said first braking element and frictionally contacts the opposite leg'of said side jamb.

11. A device in accordance with claim 8 wherein the vertical dimension of a second of the two braking elements is substantially the same as the inside vertical dimension of the casing.

12. A device in accordance with claim 7 wherein the first-mentioned braking element frictionally contacts one leg of the U-shaped side jamb and a second braking element is interlinked to said first braking element and frictionally contacts the opposite leg of said side jamb, said first and said second braking elements are mounted in a casing attached to the window sash and the vertical dimension of one of said braking elements is smaller than the inside vertical dimension of said casing and is vertically moveable in said casing.

'13. A device in accordance with claim 7 wherein the braking element is a Wedge-shaped element operatively slideable along an upwardly and outwardly inclined slide surface and adapted to wedge between said slide surface and the side jamb when in its expanded condition and References Cited UNITED STATES PATENTS 4/ 1948 Grim 49-421 5/1949 Viola et a1. 49421 8 2,543,913 .3/1951 Krouse 49-437 X 2,651,535 9/1953 Padjen 49421 X 3,407,434 10/1968 Scott 16193 I. KARL BELL, Primary Examiner US. Cl. X.R. 

